<template>
  <el-menu default-active="1-4-1" class="el-menu-vertical-demo" @open="handleOpen" @close="handleClose" :collapse="isCollapse" 
  background-color="#545c64"
      text-color="#fff"
      active-text-color="#ffd04b"
      >
      <h3>{{isCollapse? '后台':'通用后台管理系统'}}</h3> 
    <el-menu-item @click="clickMenu(item)" v-for="item in noChildren" :key="item.name" :index="item.name">
    <i :class="`el-icon-${item.icon}`"></i>
    <span slot="title">{{ item.label     }}</span>
  </el-menu-item>
  <el-submenu v-for="item in hasChildren" :key="item.name" :index="item.label">
    <template slot="title">
      <i class="el-icon-location"></i>
      <span slot="title">{{ item.label }}</span>
    </template> 
    <el-menu-item-group v-for="subItem in item.children" :key="subItem.name">
      <el-menu-item @click="clickMenu(subItem)"  :index="subItem.path">{{ subItem.label }}</el-menu-item>
    </el-menu-item-group>
    
  </el-submenu> 
</el-menu>
</template>

<script>
import router from '../router';
import Cookie from "js-cookie"
 export default {
    data() {
      return {};
 },
    methods: {
      handleOpen(key, keyPath) {
        console.log(key, keyPath);
      },
      handleClose(key, keyPath) {
        console.log(key, keyPath);
      },
      //点击菜单跳转
      clickMenu(item){
        if(this.$route.path !== item.path && !(this.$route.path === '/home' && item.path === '/'))
          {this.$router.push(item.path)}
          this.$store.commit('selectMenu',item)
      }
    },
    computed:{
        //没有子菜单
        noChildren(){
        return this.menuData.filter(item=>!item.children)
        },
        //有子菜单
        hasChildren(){
            return this.menuData.filter(item=>item.children)
        },
      menuData(){
        //判断当前数据,如果缓存中没有,则从store中获取
        return JSON.parse(Cookie.get('menu')) || this.$store.state.tab.menu
      },
      isCollapse(){
        return this.$store.state.tab.isCollapse
      }
    }
  }
</script>

<style lang="less" scoped>
.el-menu-vertical-demo:not(.el-menu--collapse) {
    width: 200px;
    min-height: 400px;
  }
.el-menu{
  height: 100vh;
  h3{
    color:#fff;
    text-align: center;
    line-height: 48px;
    font-size: 16px;
    font-weight: 400;
  }
  border:0;
}
</style>